<form action="<?php echo $_SERVER['PHP_SELF']?>" method="get">
	Name: <input type="text" name="name" />
	Adresse: <input type="text" name="adr" />
	<input type="hidden" name="secure" value="sicher" />
	<input type="submit" name="ok" value="OK" />
	<input type="submit" name="ok" value="Abbrechen" /> 
</form>

<?php 
if (isset($_GET['ok']))
{
	if ($_GET['ok'] == 'OK')
	{
		echo $_GET['name'], $_GET['adr'];		
	} 
	else
	{	
		echo $_GET['secure'];	
	}
}
?>

<?php 
// if (isset($_GET['ok']) and $_GET['ok'] == 'OK')
// {
// 	echo htmlentities($_GET['name'], ENT_QUOTES, 'UTF-8' ), htmlentities($_GET['adr'], ENT_QUOTES, 'UTF-8');
// }
// elseif(isset($_GET['secure']))
// {
// 	echo $_GET['secure'];
// }
?>